Improvement in furnaces for steam-boilers



ZSheets-She'etL J. W. BONITA. FURNACEFOR STEAM BOILER. N0,18Z.,O57,Patented Sept.12,1`875.

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JAMES w. BONTA, OE' New BRIGHTON, PENNSYLVANIA, AssIGNOR To 's BONTAnURNAon cGMP-ANY, on HARTFORD, CONNECTICUT.

IMPROVEM ENT' IN.` FU RN'EACES FQR STEAMH-BOILERS..

Specification forming-part of Letters'Patent No. 18,2.;057, datedSeptember 12, 1876; application filed.

A May 25, 1876.

To all whom it may concern:

Be it 4known that I, BONTA, of New Brighton, Pennsylvania, have inventedcertain Improvements in Furnaces for Steam;

Boilers, of "which the following` is a specification:

My improvements, which' relate to the construction of furnaces for steam-boilers, are designedto promote economy in; the consump- `tion offuel.` They accomplish thisobjectby aiordin g facilities for regulatingand-icontrolling the fire, and insuringipcrfect'and complete combustionwithout cooling the furnace by the introduction ofran excessive quantityof cold air, and without the use of drafts of 'air open at the bottomand' perforated'near thel top, automatically feeds coal upon thegratesurface as the fuel thereon `burns away, and discharges gas intothe upper part ofthe firechamber for ignition at that point 5 secondly,a` water-jacketv surrounding my magazine rei tort within thefire-chamber, and connected with Vthe'water-space of the boiler, andthus adding alarge area of available heating-surface; thirdly,inconnection with lthe magazine and retort, a' closed ash-pit, providedwithan induction pipe or pipes for supplying a jet or jets of steam orair,"or both; fourthl'y, a supplementary combustiomchamber, or aprolongation 'of-the flrechamber," provided with an induction pipe orpipes for admittingan additional `quantity -of oxygen, either in' theform of air or steam, or both; Atlfthly, a fire brick damper of peculiarconstruction, consti`- tuting the outerwall of the supplementarycombustion-chamber, and serving to `reiiec't the aming gases againstthat portion of the i boiler constituting the inner or oppositelwall ofthe supplementary combustion# chamber. These devices may be usefullyemployed either separately or two or more of them in combi nation witheach other.

Thesubjoined description explains their apy plication' to a`locomotive,"and suflicientlyin: dicates e how they can be applied to astationary boiler.

The accompanying drawings are as follows; Y Figure 1 is a centralvertical longitudinal lsection of a locomotive boiler and lfurnace withmy invention applied thereto,` Figi 2 is a transverse vertical sectionthrough the line a:

mon Fig. l. Fig. 3 is a transverse verticaly section'through Vthe line yy on Fig. `l, show#` `ingthe inner side'of the tire-brick wall'of thesupplementary combustion-chamber. Fig. l is a `front view oftheiire-brick damper-valve, together with the mechanism for rotating it,to'open and close the damper-openings. Fig. 5 is a plan of lthe rack andsegmental pinion, by which the fire-brick damper-valve is operated.Figs. 6and 7 represent details 'exhibit-- ing the construction o f theperforated fir-'ebrick damper-wall.

s Referring to the drawings, it will be seen that they represent theordinary locomotiveboiler A,"having the usual nre-chamber B, the tubesU, the smoke-chamber D, the ash-pit E, and grate F; The ash-pit isclosed, and is provided with a door, e, which tightly fits an opening,through which the contents ofthe ash-pit may be removed. Fuel issupplied to the furnace fromthe coal-magazine G the ex# ternal mouthofwhich is closed by the tight-4 itting door g.

lt will be seen that the portion of the coalmagazine within theiire-chamberis incased in the water-jacket k lt,`which is connected withthe boiler by means of the pipes and on, and is also connected with thewater-space Bl in the front wallof the fire-chamber. These connectionsof the water-jacket withthe water?. body ofthe boiler at variableelevations insure a constant circulation of water in the jacket whenthere is re in the furnace, and this device aii'ordsa large additionalheating-surface. The upper part ofthe coal-magazine within thefire-chamber is provided with one or more perforations, un', for thepurpose of` permitting the escape from themagazine of gasesgencratedfrom the coal therein contained. A convenient mode of providing theseVperforations is by the use of hollow stay-bolts, 'one of which is shownat a. The ashpit E is provided with one or more injection-pipes, f, forthe admission of blasts orjets-of air or steam, or both. Additionalinjection-pipesf2 and f3 are inserted in the furnace-wall a s hortdistance above the grate, as shown, for admitting similar blasts or jetsat that point, if desired.

A short "distancefrom the tube-sheet at the front end ot' the locomotive.is a vertical perforated fire-brick wall, K, and the space between thiswall and the tube-sheet constitutes the supplementary combustion-chamberL. The perforations in thewall K are closed or opened by the rotatingperforated fire-brick 'disk I. The latter is under the control of theengineer in the cab, being operated by means of the rod a, connectedkwith the segmental pinion b, which engages the rack c on the 'outervendof the slide-bar c', the inner end of which is pvoted to the iron frameof the valvedisk L The segment-al pinion b has its vbearings in theprojecting wing d, which isafxed to the side of the boiler A. Theperforations o in the tire-brick wall K have the same "position withrelation to each other as the perforations in the valvefdisk I, so thatby rotating the valve-disk the respective perforations may be made tocoincide in positionor other- Wlse.

'lrhe perforated 'wall K and disk I, as constructed and arranged,constitute a damper, the inner face of which reects the aming gases inthe combustion-chamber against the tube-sheet of the boiler. I thereforedesignatethe described structure as a reflectordamper. In itsconstruction re-clay, soapstone, porcelain, or other similar materialmay besub'stituted for lire-brick. The Wall K consists offour segmentsof tire-brick, or other suitablemateriah set in an iron frame, which issecured to the shell of the boiler. This frame consists ot' an iron ringhaving two or more iron cross-bars intersecting each other in the centerof the ring, and affording a bearf ing at that point for the pivot uponwhich the disk I revolves.

The disk I is composed of a similar iron frame, supporting four tlatsegmentsof lireloricks. Each of the segments of the wall K hassubstantially the shape indicated in Figs. A' 6 and 7, by reference towhich it Will be seen j that the supportingframe is wholly covered by.tl1e'iire-bricks, and that each segment S is i provided With alaterally-projectin g flange, S',

which titsl around and shields the periphery Iof the supplementarycombustion-chamber L, as shown in Fig. 1.

The object of this reflector-damper is to enable the engineer toproperly adjust and regulate the passage lfor the exit of the nitrogen-,ous or incombustible contents of thefurnace with relation to thequantity of air or steam injected into the furnace. It will, of course,

be understood that the various injection-pipes are connected with anordinary blower or airwith the reiiector-damper, or for independent usewhen the reflector-damper is allowed to remain more or less open.

In a locomotive provided with all my improvements the exhaust-pipes maybe carried to the top of the smoke-stack, as the exhaust is notrequiredfor assisting the draft. By this means there is always'a free exit forthe exhaust steam, and, therefore, no loss of power by the existence ofback pressure upon the piston arising from the choking of the exhaust.

It willbe seen that the portion of my invention embracing the combinedcoalmagazine and retort may be used in connection With a furnace havingthe ordinary draft-openings; or it may be used in connection with aclosed ash-pit and induction-pipes for the supply ot' prescribedquantities of oxygen. In either event, theoperation of this part of myinvention isv as follows: The magazine is lled with coal, and thetightttingdoor -g being closed to preventlhe escape ot' gases at thatpoint, the fuel is ignited upon the grate-bars.` As it burns away, itsplace is supplied by fuel which falls from the magazine by its owngravity. As the fuel Within the magazine is heated inflammable vapor orgases are generated, Which are discharged through the apertures n n intothe upper part of the fire-cham,- ber, where they are exposed to.ignition. The coal is thus partially coked prior to its discharge fromthe magazine. By this means the fuel is partially decomposed, and isdelivered from the magazine-retort in favorable condition for completecombustion.

It' the magazine-retort is incased in the water-jacket 7c a largeadditional area of heatingsurfaceis rendered available, and by means ofthe various connections of the water-jacket with the water-spaces aconstant circulation of the water contained in the water-jacket ismaintained, which materially assists in heating tlie water-body in theboiler. When the magazine-retort is arranged for use in combination withthe closed ash-pit and inj ection-pipes for the.-introductionof/prescribed quantitiesof;i oxygen, either in the form of air or steam,or both, the engineer injects into the ash-pit' or fire-chamber, orboth, more or less air or steam, according to the requirements of theoccasion. If he requires less heat, instead of banking his fire hereduces the supply'ofoxygen. Ifhe requires additional heat heiner'easesthe supply of oxygen, taking care not to exceed the quantity requiredfor combustion and for the displacement and expulsionof the nitrogenousor incombustible lcontents of. the lire-chamber. The induction-pipe f1delivers a supply of oxygen in favorable position for immediate mixturewith the gases discharged' fromthe retort.

It will, of course, be understood that in case of a :fire-chamber ofdifferent shape from that shown, the position of the induction-pipe f1will be varied according to the position occupied by the gases generatedin, and discharged from, the magazine-retort, the object of theinduction-pipe 4f1 being to introduce an additional supply of oxygen formixture with the gases generated in the retort to insure their completecombustion. In the locomotive-boiler `which I have described thisprinciple is further carried out by the establishment of thesupplementarycombustion-chamber,which is also provided with theinduction-pipes for supplying oxygen at that point.

The supplementary combustion chamber contributes a new element to thestructure in the reilectordamper, which constitutes its outer wall` thereflector-damper performing the double function of reiiecting theflaming gases against the tube-sheet of the boiler, and affording theengineer a means of controlling and adjusting the area of the outlet forthe incombustiblecontents of thefurnace. By means of these devices theengineer is enabled to insure in the furnace a constant supply ofoxygen, accurately graduated in quantity to the requirements of theoccasion. He is enabled to feed the furnace by depositing fuel in theexternal mouth of the coal-magazine without being under the necessity ofopening a furnacedoor, and thereby permitting a large influx of cold airinto the fire-chamber. By the use of the damper M in the smoke-stackirijconnection with the reflector-damper the engineer is enabled 'tostill more accurately regulate the outlet for the unconsumable contentsof the furnace.

I claim as my invention in a furnace for heating steam-boilers- 1. Acombined coal-magazine and retort, partially contained within thefire-chamber, open at the bottom, terminating a short distanceabove thegrate-surface, having perforations in its upper wall within thefire-chamber, and an external mouth outside the firechamber, providedwith a tight-fitting door, for the purpose of containing andautomatically delivering coal upon the grate-surface, after havingsubjected the coal to the heat of the furnace, whereby the coal ispartially cokedl prior to its delivery to the re, and the gases evolvedin the process of coking are discharged from the upper portion ofthemagazine-retort into the fire-chamber, in suitable position forcontributing by their ignition lto the heating of the boiler.

2. A magazine-retort, substantially such as described, in combinationwith a closed ashthe lire-chamber, in suitable position for immediatemixture with the gases generated and discharged from the retort,substantially as described.

4. A magazine-retort, substantially such as described, surrounded withinthe lire-chamber by a water-jacket connected at variable elevations withthe water-body of the boiler by means of suitable pipes, substantiallyas described.

5. A tire-chamber, provided with a magazine-retort, substantially suchas described, in combination with a supplementary combustion-chamber,provided with induction-pipes for supplying the said supplementarycombustion-chamber with oxygen, either in the form of air or steam, orboth.

6. The tube-sheet of a boiler, in combination Vwith the fire-brickreflector-damper, provided with mechanism whereby the damper may beopened and closed, substantially as described.

7. A perforated fire-brick wall, constituting the outer boundary of asupplementary combustion-chamber, substantially such as described, incombination with a flue or smokestack damper, substantially asdescribed.

8. A steam-boiler furnace having a closed 1 ash-pit, provided with aninduction-pipe, and a lire-chamber, also provided with an induction pipeor pipes, a magazine-retort, substantially such as described, asupplementary combustion-chamber having a pipe or pipes for theadmission of oxygen therein, and an external perforated nre-brickwal1,provided with a perforated rotating fire-brick disk, the wholeconstructed and operating substantially as and for the purposes setforth.

JAMES W. BON'IA.

Witnesses:

S. R. BowMAN, EDWIN A. ALGER.

